Wacław Florek

Abstract

In the 19th century throughout Central Europe fl oods became increasingly intense; a similarsituation pertained in the area of lake districts and the coastal zone. Maximum water levels recordedat the end of the 19th century (particularly in the years 1888-1892) to the present day on many watergaugestations (particularly those located in rivers’ lower courses) were the highest ever observed.Yet in the half on 19th century the need for regulation works became increasingly apparent. On thePomeranian rivers these works began in 1860; they reached their greatest intensity in the fi rst twentyyears of 20th century.Regulation activity was conducted which led to a distinct shortening of riverbeds; on longer sectionsof the river the reduction amounted from over 12 to 20 or more percent, in some places even50%. It caused the aggravation of bottom erosion, and also lateral erosion, which was particularlyapparent beneath the water power stations.In the last few decades the ending of work that interferes with the riverbed has resulted in thegradual restoration of the primary character of Wieprza River bed. It is also worth mentioning thateven when notable fl oods have appeared (for example, in 1980), which were comparable to those thatappeared at the end of 19th century, they did not lead to any fundamental change to any section of theWieprza River bed geosystem.

Keywords: hydrotechnic structures, Wieprza river, fl ood, river bed response, reservoir, fl oodplain.

Wacław Florek, Department of Geomorphology and Quaternary Geology, Institute of Geograpghy and Regional Studies, Pomeranian University in Słupsk, Partyzantów 27, 76-200 Słupsk, Poland
Jolanta Jaromij, Department of Geomorphology and Quaternary Geology, Institute of Geography and Regional Studies, Pomeranian University in Słupsk, Partyzantów 27, 76-200 Słupsk, Poland
Magdalena Skwierawska, Department of Geomorphology and Quaternary Geology, Institute of Geography and Regional Studies, Pomeranian University in Słupsk, Partyzantów 27, 76-200 Słupsk, Poland

Abstract

The objective of the investigation presented here has been to verify schemes for the developmentof cliff coasts proposed earlier by Subotowicz (1982). This is i.a. justifi ed by observationssuggesting greater differentiation to the geological structure and consequent hydrogeological characteristicsof the Southern Baltic cliffs than had been assumed by the authors of earlier works. Themeasurement data for the investigated profi les yielded by the work to date show that:

• the most dynamic zone on the coast is the beach,
• clifftops are the parts least resistant to destruction,
• the strong storms of late autumn 2004 and the 2005/06 and 2006/07 seasons proved capable of activatingthe cliffs at nine of the ten investigated profi les, though no relationship was found betweenthe lithology of the sediments building the cliffs and rates of erosion.

Keywords: coastal zone, cliff, Southern Baltic, extreme storms, erosion.

Wacław Florek, Department of Geomorphology and Quaternary Geology, Institute of Geograpghy and Regional Studies, Pomeranian University in Słupsk, Partyzantów 27, 76-200 Słupsk, Poland
Jacek Kaczmarzyk, Department of Geomorphology and Quaternary Geology, Institute of Geograpghy and Regional Studies, Pomeranian University in Słupsk, Partyzantów 27, 76-200 Słupsk, Poland

Abstract

In the investigations of the post-glacial development of river valleys and of theevolution of their channels the rivers flowing from the Pomeranian area directly into theBaltic Sea were generally left out. It does not mean, however, that there are no studiesconcerning the geological structure and the geomorphology of river valleys in this area.But most of those studies have a general character (cf. Deecke 1911; Biilow 1930;Keilhack 1930; Sylwestrzak 1973. 1978a. b; Piasecki 1976, 1982). The common featureof those studies is that they are but little supported by field investigations. B. Rosa(1964) has made an attempt at a comprehensive solution of the problem of thegeological structure of littoral river valleys; making use of geological archivals and ofhis own observation he has presented his views on the development of littoral rivervalleys and the problems to be solved. He has identified rather large sections ofaccumulation in the valley bottoms of littoral rivers (50 km for the Slupia, 13 km for theLupawa), as well as the effect of the sea level fluctuations on the development of organiccovers in the valley bottoms.In their studies of the Radunia valley Rachocki (1973, 1974, 1981) and Koutaniemiand Rachocki (1981) have noticed the role of late-glacial lakes in the development ofriver valleys and they have afforded important information concerning the features offluvial deposits, the rate of fluvial processes and the effect of hydrotechnical interferencein the river channel on the course and rate of those processes.The Pleistocene developmental stage of the catchment area of the Slupia and itsvalley has been lately the subject of Mojski and Orlowski's (1978) and of Orlowski's(1981, 1983) studies. They have been based on the existing geological material and on adetailed analysis of morphologic conditions.It seems, however, that the present state of knowledge on the postglacial stage oflittoral river valleys development has been correctly evaluated by Kondracki (1978) andMarsz (1984) who have indicated that, up to now, the development of no littoral rivervalley has been studied.In 1981 — 1985 at the Department of Geography of the High School of Pedagogy,Słupsk, the present author supervised work on the following subject: "The evolutionand mechanism of transformation of the valley bottoms of the Słupia and the Lupawa".It was part of the interdepartmental problem MR 1/25: "Transformation of Poland'sgeographical environment" coordinated by Professor Leszek Starkel. Substantial helpin this research was brought by the High School of Pedagogy in Słupsk, which financeda part of the radiocarbon dating and some other specialistic work.

The study was carried out with reference to the program IGCP No 158 A"Palaeohydrologic changes in the temperate zone during the last 15000 years",subproject A: "Fluvial environment". A guide-book for investigations, prepared andpublished by Starkel and Thornes (1981) has proved to be extremely useful.During their work the authors taking part in the investigations published orprepared for print a number of studies (Orłowski 1981; E. Florek 1983, in press;E. Florek, W. Florek, in press; W. Florek 1983, in press a, b, c; Alexandrowicz et al., inpress). Further studies are being prepared.

Wacław Florek, Department of Geomorphology and Quaternary Geology, Institute of Geograpghy and Regional Studies, Pomeranian University in Słupsk, Partyzantów 27, 76-200 Słupsk, Poland